Trailer 6 on 5.5" B.C. Hub Drum Kits with 12"x2" Electric Brakes for 5200-6000 Lbs Axle 2x Trailer 6 on 5.5" B.C. hub drum Kits + 2x 12"x2" electric brakes for 5200-6000 Lbs Axle Bolt pattern: 6 on 5.5"; 1/2"-20 studs and bearing races installed Kit also include: 2x 25580 inner cone bearings and 2x 15123 outer cone bearings, 2x Grease seals 2.25" x 3.371", 2x EZ lube grease caps with rubber plug, 12 cone wheel nuts 1/2"x20 thread Also include: One right and one left 12" x 2" electric brakes with 3-1/4" center hole Ref drum part #. 008-201, 42656; ref brake part #. K23-180-00, K23-181-00